Known lock units, as described in DE 10 2007 003 948 A1, consist of a rotary catch, a first pawl with a pawl rotation axis, and a blocking lever, where in the locked position the catch transfers a pivoting moment onto the first pawl, which is fixed by the blocking lever. In that, the catch transfers an opening moment onto the pawl. Furthermore, a second pawl is provided, which is mounted to the pawl rotation axis and which may be engaged with the pawl via a blocking lever. In this embodiment the first pawl forms a so-called fully-closed stop pawl, the second pawl forms a so-called preliminary-closed stop pawl. Usually, the lock unit is at the same time activated through a second pawl which during the opening process normally deviates the blocking lever so that the catch on its own pushes away the first pawl as soon as the blockage is released.
From DE 10 2008 061 524 A1, a lock unit of the generic kind is known, which consists of a spring loaded catch, a pawl, and a blocking lever for the pawl, with an opening moment towards the catch, so that the lock positions fully-closed stop and preliminary-closed stop may be accomplished by means of only one pawl with a blocking lever. Consequently, there is no need for a second pawl.
The lock unit according to DE 10 2009 029 674 A1 also does without a second pawl and in addition is designed in a way that it blocked the pawl in preliminary-closed stop as well as in fully-closed stop, however, without a positive locking of the catch and the pawl in both positions. Such lock units have already been produced in high quality and serial production and have proved particularly with regard to operational comfort and noise development.